Supremacy Clause

The Supremacy Clause of the United States Constitution (Article VI, Clause 2) establishes that the Constitution, federal laws made pursuant to it, and treaties made under its authority, constitute the supreme law of the land. It provides that state courts are bound by the supreme law; in case of conflict between federal and state law, the federal law must be applied. Even state constitutions are subordinate to federal law. In essence, it is a conflict-of-laws rule specifying that certain national acts take priority over any state acts that conflict with national law. In this respect, the Supremacy Clause follows the lead of Article XIII of the Articles of Confederation, which provided that "Every State shall abide by the determination of the United States in Congress Assembled, on all questions which by this confederation are submitted to them." A constitutional provision announcing the supremacy of federal law, the Supremacy Clause assumes the underlying priority of federal authority, at least when that authority is expressed in the Constitution itself. No matter what the federal government or the states might wish to do, they have to stay within the boundaries of the Constitution. This makes the Supremacy Clause the cornerstone of the whole American political structure.

This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing [sic] in the Constitution or Laws of any State to the Contrary notwithstanding.

In Federalist No. 44, James Madison defends the Supremacy Clause as vital to the functioning of the nation. He noted that state legislatures were invested with all powers not specifically defined in the Constitution, but also said that having the federal government subservient to various state constitutions would be an inversion of the principles of government, concluding that if supremacy were not established "it would have seen the authority of the whole society everywhere subordinate to the authority of the parts; it would have seen a monster, in which the head was under the direction of the members".

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